Prosthetic heart valve having fabric suturing element

ABSTRACT

A prosthetic heart valve is disclosed having a support ring which carries means for retaining a movable closure element in positions adjacent one side of the ring. The support ring has a fabric wrapping which defines, as a suturing element, an annular protrusion of fabric of double thickness extending from the side of the ring which is opposite the side adjacent the closure element.

United States Patent 1151 Magovern et al.

[ PROSTHETIC HEART VALVE HAVING FABRIC SUTURING ELEIWENT [75] Inventors:George J. Magovem; Harry W.

Cromie, both of Pittsburgh, Pa.

[73] Assignee: Baxter Laboratories, Inc Morton Grove, Ill.

[22] Filed: Dec. 29, 1970 [21] App1.No.: 102,347

[52] I US. Cl ..3/1, 3/DIG. 3 [51] Int. Cl. ..A61f 1/22 [58] Field ofSearch ..3/l, DIG. 3

[56] References Cited UNITED STATES PATENTS 3,524,202 8/1970 Cromie..3/1 3,263,239 8/1966 Edwards et al. .....3/1 3,548,418 12/1970 Angel]et al. ..3/l

OTHER PUBLICATIONS A New Mitral Valvet by D. E. I-larken et al., Journalof Thoracic & Cardiovascular Surgery, Vol. 55,

' [111 3,725,961 51 Apr. 10, 1973 No. 3, March 1968, pages 369-382.

Mitral Prostheses: Construction and A Standard for Evaluation by J. M.Matloff et al., Prosthetic Heart Valves, Editor-in-Chief Lyman A. BrewerIII, M.D., Charles C. Thomas Publisher, Springfield, Ill., 1968, pages148156. (Copyright 1969).

The Experimental and Clinical Results of a Modified Cage Disc MitralProsthesis" by G. J. Magovem et al., Journal of Thoracic &Cardiovascular Surgery, Vol. 59, No. 1, January, 1970, pages 109-116.

Primary Examiner-Wi1liam E. Kamm Assistant Examiner-Ronald L. FrinksAttorney-W. Garrettson Ellis [5 7] ABSTRACT A prosthetic heart valve isdisclosed having a support ring which carries means for retaining amovable closure element in positions adjacent one side of 'thering. Thesupport ring has a fabric wrapping which defines, as a suturing element,an annular protrusion of fabric of double thickness extending from theside of the ring which is opposite the side adjacent the closureelement.

6 Claims, 8 Drawing Figures PATENTEUAPR 1 01973 SHEET 2 OF 3 frzuerziard6607396 MQQ arr 52 7% j BACKGROUND OF THE INVENTION While a largevariety of prosthetic heart valves have been experimentally used, and anumber of types are commercially available, there still remain problemswhich have yet to be solved to the complete satisfaction of the surgeon.First, while it is desirable for heart valves to be generally circularin shape to permit the closure element to rotate during use in order tominimize uneven wear, the site within the heart to which the valve isaffixed is frequently oval in shape. Hence, the tissue at the site towhich the valve is-affixed must be forced to assume the circular shapeof the valve by suturing. This creates stress uponthe tissue, which is,of course, undesirable.

Additionally, partly because of the stress on the tissue, and in orderto minimize the possibility of leakage about the valve, the sutures aretypically emplaced by an interrupted technique for maximum reliability.Such a technique is time consuming and inconvenient.

The valve of this invention carries on one side thereof a suturing cuffwhich is of adjustable shape to fit the natural contour of the suturingsite within the heart. Furthermore, because of the unique manner inwhich the prosthetic valve of this invention can be emplaced in theheart, with the valve rim being spaced from the suture site, thesuturing cuff provides an added sealing function which greatly reducesthe possibility of blood leakage about the prosthesis. This permits theuse of more desirable continuous suturing techniques.

While it has been taught (e.g., Annals of Thoracic Surgery, Vol. 8, No.8, (1969), p. 133-145) to use a single layer skirt to overlie the sutureline which affixes the valve in place, the advantages described aboveare not achieved by this latter technique as effectively as in thepresent invention.

DESCRIPTION OF THE INVENTION In accordance with this invention, aprosthetic heart valve is provided having a support ring which carriesmeans for retaining a movable closure element adjacent one side of thering. The ring has a fabric wrapping which defines, as a suturingelement, an annular protrusion of fabric of double thickness extendingfrom the side of the ring opposite the side men tioned above adjacentthe closure element. The fabric wrapping is typically a folded and sewntubular sleeve in which the annular fabric protrusion is maintained indouble thickness configuration by a sewn seam. Typically, the fabricused is a velour material made from polyester fiber or the like.

In the drawings,

FIG. 1 is an elevational view of a prosthetic heart valve with portionspartly broken away, and shown in section, the sectional portioncorresponding to the view along line 1-1 of FIG. 2.

FIG. 2 is a bottom plan view of the same prosthetic heart valve withportions partially broken away and shown in section.

FIG. 3 is a partial sectional view of a portion of the prosthetic heartvalve of this invention shown in an intermediate stage of assembly.

FIG. 4 is a partial sectional view of the same portion of the heartvalve in a further stage of assembly.

FIG. 5 is a partial sectional view of the same portion of the valve incompleted form.

FIG. 6 is a detailed view, partially in section, of a portion of a strutencased in a portion of the support ring.

FIG. 7 is an elevational view, with a portion broken away and sectioned,of the support ring prior to as- Y sembly.

FIG. 8 is a diagramatic view of a prosthetic heart valve of thisinvention sutured in position in a heart.

Referring to FIGS. 1 and 2, a mitral valve is shown which utilizes theinvention of this application. The valve has a support ring 10 having across-sectional shape as illustrated in FIG. 1. Support ring 10 servesto define the shape of the body of the heart valve and the centralopening 11 defined therein, and is a support for its cloth covering andfor the means for retaining a movable closure element described below.If desired, support ring 10 can be oval in shape to more closelyaccommodate the natural shape of the suturing site.

Ring 10 carries-a pair of struts 112, which struts retain a movableclosure disc 14, which is typically made of pyrolytic carbon. Disc 14 ismovable between an open, flow-permitting position as shown in full linesof FIG. I and a closed, flow-occluding position as shown in dotted linesin the same Figure.

Ring 10 has a toroidal fabric wrapping 16 which defines, as a suturingelement, an annular protrusion 18 of fabric of double thicknessextending from the side ring 10 opposite the side adjacent the closuredisc 14. Double thickness suturing element 18 is used to suture thevalve in position within the mitral orifice as shown in FIG. 8, with theresultant advantages described above. The double thickness of suturingelement 18 provides added strength and sealing capability, to avoidblood leakage about the valve. The body of the valve, including ring 10,struts l2, and disc 14, typically hang below the hearts mitral ring inthe ventricle, as shown in FIG. 8'. If desired, a continuous suturetechnique can i be used to affix suturing element 18 to the mitral ring,

with the suturing element 18 being generally deformed outwardly asshown, to provide a better seal against blood leakage. With each pulseof blood pressure, suturing element 18 is pressed outwardly against themitral ring for additional sealing capability.

Each strut 12 contains an internal rod 20 (FIG. 6), typically oftitanium, which can be enclosed in a sheath 22 which is made of hard,nonthrombogenic plastic such as polytetrafluoroethylene. Strut 12comprises a disc-holding portion 24 outside of ring 10, and a pair ofretained portions 26 which fit within a channel 21 defined in ring 10for securance to the ring. An outer, annular flange 28 of ring 10 isbent inwardly to secure each of the retained portions 26 of strut 12 inplace.

Since the annular channel 21 (FIG. 3) defined in ring 10 is notcompletely filled after emplacement of the strut 12, an additional pairof curved filler rods 30 are supplied to fill the remaining space of thechannel 21.

Retained portions 26 of the struts and curved filler rods 30 are heldtogether in a subassembly by means of support ring 32, which isinitially of U-shaped cross section, as shown in FIG. 7. Support ring 32has slots 34 defining tabs 35, which can be folded over retainedportions 26 and curved filler rods 30. Appropriate cutaway portions ofsupport ring 32 and flange 28 are provided to permit the struts 12 topass out of the ring at the points where disc-holding portions 24 aredefined.

Ring carries an annular seat 36 against which closure disc strikes andseals when in the closed, flow-occluding position. Seat 36 includes acircular strip of flexible adhesive 38 (FIG. 3) which is typicallysilicone rubber. Adhesive 38, in turn, holds a circular strip 40 ofdacron felt or the like, to provide a relatively resilient seat overwhich fabric 16 passes and against which disc 14 strikes as it closes.

Referring to FIGS. 3 through 5, a technique for assembling the valve ofthis invention is shown.

A tubular piece of dacron velour or the like is sewn together along acircular seam 42 to define suturing element 18. The sewn tubular fabricmaterial 16 is then placed over support ring 10 in the manner indicatedin FIG. 3, and ends 44, 46 are sutured together with a second circularseam 48 and pushed upwardly into channel 21 defined in ring 10 asindicated in FIG. 4. The dimensions of tubular fabric 16 are so selectedthat a firm fit of fabric is achieved about ring 10. Following this, thesubassembly made of struts 12, curved filler rods 30, support ring 32,and disc 14 is also inserted into channel 21 defined in ring 10. Fingers50 of flange 28, which are separated by channels 52, are pushed inwardlytoward the center of ring 10 to affix the subassembly held together bysupport ring 32 in ring 10. Prior to insertion of the subassemblyincluding support ring 32 into channel 21, disc 14 has been incorporatedinto the subassembly, so that bending of fingers 50, as indicated inFIG. 5, results in the completed heart valve as shown in FIGS. 1 and 2.

The above disclosure has been for illustrative purposes only and is notintended for purposes of restriction of the invention, which is definedin the claims below. While a single type of heart valve has beendisclosed herein, the invention of this application is contemplated foruse with any of a large variety of valves for use in the heart or forother uses, including all types of aortic as well as mitral valves. Somespecific types of valves in which the invention of this application canbe used include other discoid valves, such as those with struts whichcross each other to define a cage-like enclosure about the movable disc,valves using movable occluder balls, or valves with poppet occludersconnected to a projecting neck and slidably held in a retention ring,such as the valve shown in issue of The Lancet published Sept. 24, 1962,page 1087.

Tilting disc valves such as those shown in US. Pat. No. 3,476,143, canalso be built in accordance with this invention. Likewise, differentfabric wrappings and other configurations can be used in valves made inaccordance with this invention, such as in the valves described'in U.S.Pat..Nos. 3,099,0l6 and 3,263,239.

That which is claimed is:

1. A prosthetic heart valve which comprises: a support ring defining anorifice, which support ring carries means retaining a moveable closureelement adjacent one side of said support ring, said support ring havinga fabric wrapping which defines, as a suturing element, a flexibleannular protrusion. of fabric of multiple thickness extending solelyfrom a radially inward portion of the side of the support ring inposition adjacent the orifice, and positioned opposite said one sideadjacent the closure element, said protrusion extending in a directionapproximately perpendicular to the plane of said support ring, and anannular seam securing together the thickness of fabric defining saidannular protrusion.

2. The heart valve of claim 1 in WhlCh said fabric wrapping is a foldedand sewn tubular sleeve.

3. The heart valve of claim 2 in which the annular fabric protrusion isof double thickness.

4. The heart valve of claim 3 in which said fabric is velour whichcomprises polyester fiber.

5. The heart valve of claim 4 in which said movable closure element is adisc which is movable between an open, flow-permitting position and aclosed, flow-occluding position.

6.-A prosthetic heart valve which comprises a support ring defining anorifice, which support ring carries means retaining a moveable closureelement adjacent one side of said support ring, said support ring havinga fabric wrapping which defines, as a suturing element, a flexibleannular protrusion of fabric of multiple thickness extending solely froma radially inward portion of the side of the support ring in a positionadjacent the orifice, and positioned opposite said one side adjacent theclosure element, said protrusion extending in a direction approximatelyperpendicular to the plane of said support ring and having inner andouter ends, an annular seam securing the thickness of fabric definingsaid annular protrusion of fabric together adjacent said inner end, andsutures in the outer end of said protrusion for securance to a mitralorifice of a heart, the outer periphery of said support ring being freeof tissuesecuring sutures.

1. A prosthetic heart valve which comprises: a support ring defining anorifice, which support ring carries means retaining a moveable closureelement adjacent one side of said support ring, said support ring havinga fabric wrapping which defines, as a suturing element, a flexibleannular protrusion. of fabric of multiple thickness extending solelyfrom a radially inward portion of the side of the support ring inposition adjacent the orifice, and positioned opposite said one sideadjacent the closure element, said protrusion extending in a directionapproximately perpendicular to the plane of said support ring, and anannular seam securing together the thickness of fabric defining saidannular protrusion.
 2. The heart valve of claim 1 iN which said fabricwrapping is a folded and sewn tubular sleeve.
 3. The heart valve ofclaim 2 in which the annular fabric protrusion is of double thickness.4. The heart valve of claim 3 in which said fabric is velour whichcomprises polyester fiber.
 5. The heart valve of claim 4 in which saidmovable closure element is a disc which is movable between an open,flow-permitting position and a closed, flow-occluding position.
 6. Aprosthetic heart valve which comprises a support ring defining anorifice, which support ring carries means retaining a moveable closureelement adjacent one side of said support ring, said support ring havinga fabric wrapping which defines, as a suturing element, a flexibleannular protrusion of fabric of multiple thickness extending solely froma radially inward portion of the side of the support ring in a positionadjacent the orifice, and positioned opposite said one side adjacent theclosure element, said protrusion extending in a direction approximatelyperpendicular to the plane of said support ring and having inner andouter ends, an annular seam securing the thickness of fabric definingsaid annular protrusion of fabric together adjacent said inner end, andsutures in the outer end of said protrusion for securance to a mitralorifice of a heart, the outer periphery of said support ring being freeof tissue-securing sutures.